The issue was reported at about 9:30 a.m. Trolley service was up and fully running again by noon.

At noon, a rider at the Gateway station told Channel 4 Action News reporter Janelle Hall that he had been waiting about two hours to go to the North Side.

"I was downtown at 9:30, 10 this morning, and we're just now getting through," he said. "With a little 10-month-old baby, it makes things a little frustrating. We're very thankful (it's open again)."

While shuttle buses served riders between Downtown and the North Shore, spokesman Jim Ritchie said workers were sent to each ventilation control inside the tunnels to turn them on.

WTAE Channel 4 Action News found a crowd of frustrated riders outside the Gateway station during the closure.

"Not only this station is closed, but the Wood Street station is closed, and the Port Authority isn't making it any better. They're not helping us to get around town," Gloria Heards said. "If people had common sense, they would have brought us a shuttle in here and shuttled us back across to the North Side."

"There's one coming to the North Side now, but we've been here for an hour waiting for one. It was very inconvenient to wait an hour, and I'm going to be late. It's too much trouble," Melissa Connolly said.